Time standards are now based on atomic clocks. A promising second standard is based on pulsars, which are rotating neutron, stars (highly compact stars consisting only of neutrons). Some rotate at a rate that is highly stable, sending out a radio beacon that sweeps briefly across Earth once with each rotation, like a lighthouse beacon. Pulsar PSR 1937 + 21 is an example; it rotates once every 1.557 806 448 872 75 ± 3 ms, where the trailing + 3 indicates the uncertainty in the last decimal place (it does not mean t3 ms).

(a) How many rotations does PSR 1937 + 21 make in 7.00 days?

(b) How much time does the pulsar take to rotate exactly one million times and

(c) What is the associated uncertainty?